When someone decides to stop using drugs or alcohol, detox is usually the first hurdle. For families watching from the outside, this period can be frightening and deeply confusing. What is actually happening? Is it dangerous? How long will it last? And what can you do? Understanding the process makes it easier to provide the right kind of support at the right moment.

What Is Detox?

Detoxification — detox — is the process by which the body clears itself of a substance after dependence has developed. When someone has been using heavily over a period of time, their brain and body adapt to the constant presence of that substance. Receptors adjust. Chemistry shifts. The body comes to treat the drug as part of its normal functioning.

When the substance is removed, the body reacts to its absence. That reaction is withdrawal. Depending on the substance, the length and intensity of use, and the individual’s physiology, withdrawal can range from mild and flu-like to severe and life-threatening.

It is important to understand what detox is not. Detox is not rehabilitation. It is not recovery. It is the physical clearing of the substance from the body. What comes after — addressing the psychological, behavioural, and underlying causes of addiction — is where the real and lasting work of recovery happens. Detox alone has a very high relapse rate.

Withdrawal by Substance

• Alcohol: Sweating, trembling, nausea, anxiety, severe insomnia — and in serious cases, potentially fatal seizures or delirium tremens (DTs). Alcohol withdrawal is one of the few that can be directly life-threatening and always warrants medical supervision in heavy drinkers.
• Opioids (heroin, fentanyl, prescription painkillers): Severe flu-like symptoms — extreme muscle aches, vomiting, diarrhoea, chills, insomnia, profound anxiety. Intensely uncomfortable and demoralising, but rarely life-threatening in otherwise healthy adults. The risk is relapse during or after withdrawal, which — after even a short period of abstinence — dramatically increases overdose risk.
• Benzodiazepines (Xanax, Valium, Klonopin): Carries similar seizure risk to alcohol and requires careful medical management. Never attempt cold turkey. A gradual taper under medical supervision is the standard approach.
• Stimulants (cocaine, methamphetamine): Primarily psychological withdrawal — severe depression, profound fatigue, intense cravings, irritability. Rarely medically dangerous but psychologically brutal.
• Cannabis: Irritability, sleep disruption, appetite loss, mild anxiety. Uncomfortable but not medically dangerous.

Medical Detox vs Detoxing at Home

Medical detox takes place in a hospital, detox facility, or residential treatment centre where withdrawal is actively managed by doctors and nurses. Medications — including benzodiazepines for alcohol withdrawal, buprenorphine or methadone for opioids, and various comfort medications for symptoms — are used to ease the process and prevent dangerous complications.

Home detox is sometimes appropriate for lower-risk situations — cannabis withdrawal, mild stimulant use, very mild alcohol dependency — but should never be attempted for heavy alcohol use, benzodiazepine dependency, or severe opioid addiction without medical guidance and supervision.

How Long Does Detox Take?

• Alcohol: Symptoms typically begin 6–24 hours after the last drink, peak at 24–72 hours, and largely resolve within a week. Post-acute withdrawal (sleep disruption, anxiety) can continue for weeks.
• Short-acting opioids (heroin): Symptoms begin 8–24 hours after the last use, peak at 36–72 hours, largely resolve in 5–7 days.
• Long-acting opioids (methadone, extended-release prescriptions): Slower onset, longer duration — symptoms can persist for two to three weeks.
• Benzodiazepines: Highly variable depending on the specific drug and duration of use. A medically supervised taper can take weeks to months.
• Stimulants: The acute “crash” typically resolves within a week. Mood disturbance and cravings can persist for weeks or months.

For a more detailed breakdown by substance: How Long Does Drug Withdrawal Last? →

What Families Can Do During Detox

• If they are in a medical facility, follow the programme’s guidance on visits and contact — some deliberately limit these to support focus and reduce the pull of outside relationships during the most critical phase
• Do not minimise what they are going through. Withdrawal is physically brutal and emotionally terrifying. Validating the difficulty without offering escape from it is the right balance.
• Prepare a simple, comfortable environment for when they return home — clean space, easy food, minimal demands and expectations
• Resist the urge to celebrate completion of detox as though it were completion of recovery. It is not. It is the beginning.
• Have the next step clearly in place before they leave medical supervision — therapy, outpatient programme, sober living, NA meetings. The gap between detox and treatment is one of the highest-risk periods for relapse.

Detox Is a Beginning, Not an End

The majority of people who complete detox without follow-up treatment relapse within days or weeks. The body is cleared of the substance, but the psychological dependence, the triggers, the habits, and the underlying reasons for use remain entirely intact. Detox addresses the physical. Recovery addresses everything else.

See our guide: Drug Addiction Treatment Options: A Family Guide →